Moving through space has always been one of the main dreams of mankind. Many machines have been produced, each more sophisticated than the last, which aim to achieve this dream with greater or lesser success.
Thus, in order to attempt to move with ease through environments as diverse as the surface of water or in contact with a sometimes hostile environment, a propulsion device such as described in the 1960s in U.S. Pat. Nos. 3,243,144 or 3,381,917 comprises a body in the form of a harness or a seat on which or in which a passenger can be positioned. Such a body engages with a thrust unit in particular in the form of a pair of nozzles for ejecting a fluid under pressure and thus to generate a thrust force. In order to simplify the flight of the passenger and to reduce the physical effort thereof, the nozzles are arranged above the centre of gravity of the body-passenger assembly, specifically at the height of the passenger's shoulders. The unit also includes a fluid-compression station supplied with flammable liquids or gases and positioned on the back of the passenger. Said station is capable of supplying enough thrust to cause the passenger to take off, transformed into a type of human rocket. The low operating range coupled with the dangerousness of such devices have caused them to remain relatively confidential.
More recently, a device such as describes in U.S. Pat. No. 7,258,301 and US patent application 2008/0014811 A1 draws inspiration from said teaching, adapting it to reduce the dangerousness of the system. The compression station in this case is remote and generally dedicated. Furthermore, the pressurised fluid is water compressed by said station, drawing inspiration in this regard in particular from experiments aiming to use compressed water to reduce the physical effort of a deep-sea diver, as suggested in U.S. Pat. No. 3,277,858. U.S. Pat. No. 7,258,301 and US patent application 2008/0014811 A1 thus propose an airborne propulsion device that is similar to its predecessor, adapted such that pressurised water is transported from a remote compression station by means of a supply channel such as a fire hose. The configuration of the nozzles as well as the means that makes it possible to direct said nozzles in order to determine the trajectory of the device are deliberately kept in order to maintain certain ease of piloting for the passenger. However, in particular the take-off phase requires the passenger to be in an initial standing position, with the feet on a solid surface. The physical effort of the passenger to move, reduced to the simplest expression thereof, is detrimental to the freedom and the variety of movements on the surface of the water or under the surface thereof. Furthermore, such a “device+station” system in accordance with U.S. Pat. No. 7,258,301 is expensive due to the design of the device comprising hinged nozzles, and to the design of a dedicated compression station. The fact of being able to move through space has an intrinsic recreational side. However, the configuration of the nozzles located above the centre of gravity of the device gives the passenger the impression of hanging by the shoulders from a virtual crane hook, and thus deprives the passenger of many sensations: falls, improvised or acrobatic style figures. Furthermore, the variety of directions and movements is limited. It is not easy, for example, to move “crabwise” with a known device, or to change instantly from a straight trajectory on the surface of the water to a diving phase followed by multiple movements under the surface of the water.